Water-tube boiler.



PATENTED AUG. 18, 1903.

G. SILVESTRI.

WATER TUBE BOILER.

APPLICATION FILED mo. 23, 1902.

2 SHEETS-SHEET 1.

I0 MODEL.

N j W) fiilizersaw No. 736,451. PATENTED AUG. 18, 1903.

G. SILVESTRI.

WATER TUBE BOILER. APPLIOATIQfI FILED D30. 23, 1902.

N0 MODEL.

" z sums-sum 2.

Jib/72%- UNITED STATES iatented August 18, 1903,.

PATENT OFFICE.

WATER-TUBE BOILER.

SPECIFICATION forming part of Letters Patent No. 736,451, dated August18, 1903.

Application filed December 23,1902. Serial No. 136344. (No model.)

To all whom it may concern,-

Be it known that I, GIULIO SILVESTRI, a citizen of Austria-Hungary,residing at Vienna, in the Province of Lower Austria, Empire ofAustria-Hungary, have inventedcertain new and useful Improvements inVater- Tube Boilers, of which the following is a full, clear, and exactspecification.

This invention relates to a new orimproved water-tube boiler, and hasspecial reference to that class of water-tube boiler in which a fluesuitable for the employment of an internal furnace or fireplace iscreated by providing water-tubes in close contact to one another and itconsists in particular in arranging concentrically two or more rows ofsuch water-tubes in such manner that they formfluesandannulartubes,respectively,arranged within one another, the mostcentral one of such flucs being intended for the reception of thefireplace, while the annular spaces between the individual rows ofwater-tubes and between the outer row of tubes and the external jacket,respectively, serye as dues for the hot products of combustion,provision being made for the communication of the said flues with oneanother, so that the products of combustion may pass from one flue intothe other, which is effected by alternately reducing the diameter of thetube ends to any re quired extent in such manner that only one end ofeach tube is subjected to such reduction, also for suitably embeddingthe tubes by fitting the respective walls with corresponding brackets orrecesses.

The new or improved water-tube boiler is represented in the accompanyingdrawings, in which- 7 Figure 1 is avertical longitudinal sectional viewFigs. 2 and 3, cross-sections on the lines A A and B B, respectively, ofFig, 1, while Figs. 4 and 5 show in a folded-up state a section of theinner and outer tube jackets, respectively, as formed by the respectiverows of tubes.

lVith reference to the above drawings the boiler consists of two waterdrums, chambers, or tanks a and 1), preferably ring or annular shaped,the two walls 0 of which drums or chambers facing one another areadapted as tube-walls-that is to say, they serve as bedframes for therows of tubes (Z and f-while the outer front Walls of said water drums,chambers, or tanks are made so as to be re moved for the purpose ofproviding easy access to the tubes According to the invention the boileris fitted with two or more concentric rows of water-tubes arranged inclose contact to each other, the innermost or most central one of suchrows cl forming a flue and serving as such to receive an internalfireplace of any desired construction, but preferably of suchconstruction as is used in combination with liquid and vaporous orgaseous fuel, respectively, while the annular spaces It and t' leftbetween the concentric rows of tubes (Z and f and between the outer rowof tubes and the boiler-jacket g, respectively, form and serve as fluesfor the hot products of combustion. In order to enable such hot productsof combustion to pass from the grate or firechamber into the firstannular flue h and from the latter into the next annular flue i, theends of the tubes are alternately to a corresponding extent or lengthreduced in diameter-that is to say, the innermost or most central tubescl are reduced in the manner indicated at the ends abutting against thebackward or rear water chamber or tank I), the tubes forming the nextrow f at the ends abutting against the front water chamber or tank a,the next series of tubes, if any, again at the ends abutting against thebackward or rear water chamber or tank I), &c., the consequence of sucharrangement being that slits or passages n n are formed between the endsof the tubes, which serve to allow the gases of combustion to pass.Since, on the one hand, brackets or recesses must be provided betweenthe individual tubes for the purpose of embedding the latter in theabutment-walls and since, on the other, such tubes can only be reducedin diameter at one end in order to insert and exchange them, suchreductions are only applied to every other tube, the length or extent towhich they are effected corresponding to the thickness of theabutment-wall and to the cross-section of the passage to be obtained,respectively. The result of this arrangement is that the one series orgroup of tubes can be withdrawn or removed in the one direction and thesecond series or group of tubes in the other.

ICO

' tains a flue without the employment of masonry, and thereby allows ofan internal furnace or fireplace being made use of.

It is not absolutely necessary to arrange the water-tubes in theconcentric circular order as illustrated; but the arrangement thereofmay also be effected in other closed curves or in a polygonal fashion.As regards the water drums, chambers, or tanks,-they may be connected bytwo or more of such series or groups of tubes instead of by one suchseries or group, in which case boilers are created with two or morefurnaces or fireplaces.

In order that an active circulation in the boiler may be brought about,the latter may, as is usual, be slightly inclined, or, as shown in theright-hand part of Fig. 1, it may be preferable to fit a suitablecontrivance for that purpose into the short pipe or socket 1),connecting the chamber or tank I) with the steamcollector 0. The saidcontrivance consists of a plate 1, adapted to completely close the shortpipe or socket p, and into said plate is inserted a series of narrowtubes 8, the upper ends of which reach into the steam chamber orcollector 0. Said system of tubes 8 forms with the short pipe or socketp a communicating vessel for chamber or tank a. As the mixture of steamand Water particles ascending in the tubes 8 is of lower specificgravity than the liquid in the short tube or socket p, which is freefrom steam, the difference in the hydrostatic pressure will result inbringing about an active circulation in the boiler.

What I claim is 1. A steam-boiler comprising in combinationwater-chambers, and tubes arranged intermediate said chambers and seatedat their ends in the opposing heads of the chambers, said tubes beingarranged in series,one Within the other, the tubes in each series beingin close contact with each other and a space being left between thetubes in one series and the tubes in the other series, each alternatetube inthe different series having one end reduced in diameter for thepurpose specified.

2. A steam-boiler comprising in combination water-chambers and tubesarranged intermediate said chambers and seated at their ends in theopposing heads of the chambers, said tubes being arranged in concentricseries, the tubes in each series being in close contact with each otherand a space being left betweenthe tubes in one series and the tubes inthe other series, each alternate tube in the different series havingoneend reduced in diameter, for the purpose specified.

3. A steam-boiler comprising in combination water-chambers and tubesarranged intermediate said chambers and seated at their ends in theopposing heads of the chambers, said tubes being arranged in series,onewithin the other, the tubes in each series being in close contact witheach other and a space being left between the tubes in one series andthe tubes in the other series, each alternate tube in the differentseries having one end reduced in diameter, and a jacket surrounding theoutermost series of tubes with a space intermediate said latter tubesand said jacket.

4. A steam-boiler comprising in combination water-chambers, and tubesarranged intermediate said chambers and seated at their ends in theopposing heads of the chambers, said tubes being arranged in series onewithin the other the tubes in each series being in close contact witheach other and a space being left between the tubes in one series andthe tubes in the other series, the tubes in the different series havingtheir alternate ends reduced in diameter, for the purpose specified.

In testimony that I claim the foregoing as my invention 1 have signed myname in presence of two subscribing witnesses.

GIULIO SILVESTRI.

Witnesses:

WILHELM BERGER, ALVESTO S. Hoenn.

